But a lot of that memory is shared between multiple processes -- on my system, gvfsd is linked to many libraries like libdbus-1 and libc and libpthread that are also used by many other processes. Shared libraries like those only need to be loaded once, and all processes that need them use the same copy in memory -- but this inflates the memory usage reported.

If you add some info on what utility gave you that memory usage number, we can give more details about where the number came from.